Energy absorption devices are used for the purpose of absorbing as much energy as possible in the event of an accident, before the vehicle body of the vehicle plastically deforms. In less severe accidents, the energy absorption capability of an energy absorption device may be sufficient to entirely avoid plastic deformation of the vehicle body. The repair costs remain low in this way, because only the bumper and the energy absorption device have to be replaced.
For good energy absorption, it is optimal if the energy absorption devices are implemented as an extension of longitudinal girders of an underbody of the vehicle and the bumper, in particular its crossbeam, is located horizontally at the height of the energy absorption devices. The forces are thus introduced linearly into the energy absorption device, by which its entire length may be used well for the deformation, i.e., absorbing energy.
The vehicle manufacturers have made efforts to bring as many vehicle variants as possible onto the market. To keep the costs as low as possible, the various vehicle variants are constructed on one underbody. If sports utility vehicles or SUVs are constructed on a passenger automobile underbody, the underbody is higher than in the passenger automobile. According to the legal requirements, however, the bumper, in particular its crossbeam, must be located at the height which normally corresponds to a passenger automobile bumper. This means that a Vertical offset between the bumper, in particular its crossbeam, and longitudinal girders of the underbody is to be bridged.
One possibility is to implement the energy absorption device, as up to this point, as a longitudinal extension of the longitudinal girder of the underbody, but provide a bumper with a cross member which extends over the entire vertical area and is implemented as solid. In this way, the forces may be introduced into the energy absorption device well and absorbed thereby.
Generic, or type-specific energy absorption devices are also known and used to bridge the offset between the bumper, or a cross-member of the bumper, and the longitudinal beam of the chassis. More compact and lighter bumpers, in particular their cross-members, may thus be used for a weight reduction. However, tests have shown that accident forces are not conducted straight enough through such energy absorption devices, which amounts to poor energy absorption.